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512                                     THE IRON INDUSTRY.
band, but the price had risen to $3.60 per ton at the pit. In 1900 only 597,826 tons of ore were raised from the coal measures, the price being officially given as $2.40 per ton at the pit mouth, and this constituted 70 per cent, of all the ore raised in Scotland.
The'pig-iron industry, in spite of the disappearance of the black-band and the importation of foreign ores, still retains a distinctive characteristic in the use of raw "splint" coal in the blast furnace. The composition of Lanark coal is as follows:
Per cent.
C......................................    66.00
H......................................      4.34
0+N....................................    12.03
S......................................      0.59
Ash....................................      5.42
Water ..................................    11.62
100.00 Fixed carbon............................    53.4
This coal, when charged into the furnace, will not fuse and get sticky, provided the furnace is not more than 70 feet high. The heating value is only 80 per cent, of Durham coal, but counting the loss in the coking process, there is a slight advantage, ton for ton, in the Scotch coal charged in the furnace over the Durham coal, which must first be coked. When using this raw coal the furnace gases contain a quantity of hydrocarbons, and it is profitable to put up scrubbers and collect the tar and ammonia before the gas passes to the boilers and stoves. The best beds of Lanarkshire coal are approaching exhaustion, and recently some plants have experimented in the making of a poor coke from local coal and using it as a mixture with the inferior splint coals, but this practice seems to make no progress. A considerable amount of coke is
TABLE XXIII-I. Production of Pig-Iron in Scotland.
Period.                                           Production per year.
Inclusive.                                                     Tons.
1861 to 1865...................___'.,;    1,122,600
1866 to 1870..........................    1,089,800
1871 to 1875..........................     1,021,600
1876 to 1880..........................       993,600
1881 to 1885..........................    1,084,400
1886 to 1890.........,................        922,217
1891 to 1895.....'.....................         826,128
1896 to 1900..........................     1,128,161
1901 to 1903..........................     1,232,967,